1) Field of the Invention
The present invention relates to an automatically retractable safety syringe, more particularly to a syringe designed to be operated by single hand and to have an automatically retractable needle assembly not allowing for reuse.
2) Description of the Prior Art
Nowadays, since syringes have been widely used to inject medicine all around the world, needle sticking related injuries occur quite often; the sequelae caused by this kind of accident should not be overlooked because more than twenty kinds of diseases are infected through blood transmission, for example, HIV-1 (AIDS), Hepatitis B and C; it requires a considerable society cost for handling the follow-ups after injury accidents. The prior art safety syringe is usually operated manually by both hands; although the manufacturing cost thereof is low, its application is inconvenient and not safe enough either.
In view of the abovementioned needle stick injuries and shortcomings of the prior art safety syringe, the primary objective of the present invention is to provide a syringe designed to be operated by single hand, to have an automatically retractable needle assembly not allowing for reuse; the said automatically retractable safety syringe comprises a needle assembly with a cannula a needle hub and a rubber O-ring thereof, a needle cap, a retracting spring, a breakable plunger, a plunger rubber gasket and a medicine barrel; in accordance with the structure of the said automatically retractable safety syringe of the present invention, since the breakable plunger is assembled inside the medicine barrel, after being pushed all the way to the end, it is forced to break automatically into two parts for reducing it""s length so as to provide enough space for the retracting spring to drive the needle assembly moving along the sliding passages to accomplish the automatically retracting action.
To enable a further understanding of the structural features and the technical contents of the present invention, the brief description of the drawings below is followed by the detailed description of the preferred embodiment.